Electronic transaction processing systems may utilize a payment device and a payment terminal. The payment device provides payment information to the payment terminal. The payment terminal reads payment information such as a credit card number from the payment device and transmits the payment information along with information relating to the transaction to a remote transaction server. The remote transaction server determines whether the transaction is approved and provides a response to the payment terminal. To reduce the risk of fraud, many electronic transaction processing systems now require the payment information to be encrypted. The payment information can be encrypted by the payment device or the payment terminal may encrypt the payment information (along with other transaction information) for security purposes.
The processing of encrypted payment information may be performed by a dedicated cryptographic processor in the payment terminal. While the use of the cryptographic processor can improve operation of the payment terminal by relieving the general processor of the payment terminal from having to process encrypted payment information and may protect sensitive information, the cryptographic processor may use more power than the general processor. In a situation where the payment terminal has a limited power supply, such as when a battery is used, the continuous powering of the cryptographic processor can shorten the operational life of the payment terminal, i.e., the time the payment terminal can be used before recharging of the battery is required, which, in turn, shortens the amount of time that the payment terminal can process payment transactions. If the payment terminal is unable to process payment transactions, the operator of the payment terminal may lose sales opportunities and/or have to find alternative payment systems, neither of which is beneficial to the operator.